Issue 87: suggested response to the follow-up comment

[Anish Karmarkar <Anish.Karmarkar@oracle.com>]

Here is my suggested response. Comments are welcome.

-Anish
--



On 10/7/2009 9:12 AM, Michael Champion wrote:
> Thank you for considering Microsoft's suggestion for improving the SCA
> Web Services Binding spec's interoperability
> (http://www.osoa.org/jira/browse/BINDINGS-87).
>

The TC greatly appreciate Microsoft's comments and the ongoing dialog. 
It would be even better, from an interoperability and adoption 
perspective, if Microsoft were to participate in the SCA bindings TC and 
participate/contribute to the TC's work.

> We suggested that Web Services callbacks in the SCA Web Services Binging
> spec should interoperate with comparable frameworks such as JAX-WS and
> WCF, and not be limited to various implementations of SCA. This would
> promote the original goals of the Web Services standards to achieve
> wire-level interoperability among diverse run-times and platforms.
>

There is perhaps a misunderstanding about the SCA Web Services Callback 
Protocol. There is *nothing* in the protocol that impedes wire-level 
interoperability with frameworks such as JAX-WS and WCF. The protocol 
(and the associated WSDL extension, WS-Policy assertion) uses the well 
know and well adopted WS-* architecture of composible specifications. It 
uses SOAP/WSDL/WS-Policy extensibility/architecture to implement the 
callback functionality. Any WS-* stack that allows one to handle 
extensibility/composable specification should be able to handle the 
protocol.

Perhaps you mean "out-of-the-box" interoperability from JAX-WS/WCF. If 
so, then that is the decision the implementors/creators of JAX-WS/WCF 
have to make. It is not within the scope of this TC. Since Microsoft 
owns WCF, it would be up to Microsoft to provide such an 
"out-of-the-box" interoperability, and this TC would urge Microsoft to 
do so.

**********
[This part would be included only if we decide to resolve issue 124 
along the direction that has been discussed recently. If not, this para 
will be removed.]

To that end, the TC has created separate conformance targets/sections 
that allows for entities that want to conform to the protocol, but not 
necessarily implement an SCA runtime. See resolution of issue 124 [.1]

[.1] http://osoa.org/jira/browse/BINDINGS-124

**********

> The SCA Binding TC responded by saying that the SCA Web Services binding
> protocol "defines an *SCA* Web service callback protocol standard” and
> that it "is not meant to satisfy general purpose callback requirements
> with a broadest scope possible". In other works, the TC believes that
> the SCA Web Services callbacks will NOT be interoperable with non-SCA
> implementations
>

That is incorrect. Not defining a protocol that satisfies *every* 
possible callback definition and interoperability are orthogonal.

As mentioned above, SCA Web Services Callback Protocol is interoperable 
with non-SCA runtimes as long as they implement the protocol as specified.

What we meant to say was that:
The TC is not interested in boiling the ocean to satisfy every callback 
scenario and every possible callback definition. Microsoft's comment was 
interpreted by the TC as suggesting that all the callback-related 
discussion need to be re-discussed in a separate TC and that we need to 
start from scratch. We believe that the SCA callback definition 
satisfies the needs of SCA. Furthermore the SCA callback definition is 
general enough to satisfy other needs as well. Doing so is well within 
the scope of this TC and we believe it is interoperable on the wire.

This is very similar to what the WS-RX TC [.1] did when it created a 
polling specification [.2]. Polling is necessary to implement reliable 
messaging when one of the interacting entities is behind a firewall. 
They created a specification that is useful for WS-ReliableMessaging as 
well as other WS-* implementation that have a need for polling and 
choose to use WS-MakeConnection for that purpose.

[.1] http://www.oasis-open.org/committees/tc_home.php?wg_abbrev=ws-rx
[.2] http://docs.oasis-open.org/ws-rx/wsmc/200702/wsmc-1.1-spec-os.html

> The TC's response goes on to say that "This TC does believe that it
> should define an interoperable Web services protocol that implements SCA
> callback and it has done that. It does not believe that it is in the
> scope or interest of this TC to define a callback protocol for all
> architectures and programming models."

What was meant here (and should have been said) was:
We believe that we have defined an interoperable callback protocol. It 
works for SCA and we believe it works for other architectures and 
programming models (SCA is designed ground-up for a multiple programming 
model environments).

If Microsoft believes that the SCA callback definition does not fit 
their architecture/programming model, then we respectfully request (and 
per our understanding certain members of the TC have in the past) 
Microsoft to participate in the TC. No one, including Microsoft, has 
brought forward any *specific* architectural or interoperability issues 
with the callback protocol definition.

> We respectfully find this
> statement contradictory, unless the TC defines the term
> "interoperability" in its narrowest form: SCA implementations will only
> be interoperable amongst themselves, and not with other frameworks and
> runtimes. We would find this unfortunate, as OASIS is committed to broad
> interoperability, especially when it comes to use of Web Service wire
> protocols. It would be better to standardize a Web Services callback in
> a separate spec, with the participation of all vendors who build
> platforms and products that support Web Services wire protocols.
>

Again, we would welcome Microsoft's participating in this TC.

**********
[note this paragraph depends on the resolution of issue 124]

We would also note that the spec now contains conformance requirements 
for non-SCA runtimes that would like to implement the protocol and 
interoperable on the wire.
**********

> It is clear from [1] that the TC is aware that interoperability with
> non-SCA runtimes is an issue. The TC discussed the idea of moving the
> callback portion of the protocol into its own document in order to
> address "the use case of non-SCA clients does walk into the more general
> territory alluded to by MS." We highly recommend that the Binding and
> Assembly TCs work together to design a Web Services Binding spec that is
> interoperable with non-SCA technologies. Without interoperability,
> software developers and users will find it difficult to use SCA in the
> heterogeneous, multi-vendor environments that all our customers live in.
>

**********
[note this paragraph depends on the resolution of issue 124]

Indeed, and the spec has been changed to allow non-SCA runtimes to 
conform to the protocol and interoperate on the wire.
**********

> [1]
> http://www.oasis-open.org/committees/download.php/34064/SCA%20Bindings%20minutes%202009-09-03.doc
>
> Regards,
>
> Michael Champion
>
> *From:* Simon Holdsworth [mailto:simon_holdsworth@uk.ibm.com]
> *Sent:* Thursday, September 17, 2009 7:04 AM
> *To:* sca-bindings-comment@lists.oasis-open.org
> *Subject:* [sca-bindings-comment] Response to: "Microsoft technical
> comment: Develop interoperable approach notspecific to SCA for callbacks"
>
>
> This is a formal response of the OASIS SCA Bindings technical committee
> to the "Microsoft technical comment: Develop interoperable approach not
> specific to SCA for callbacks" which was sent to the SCA Bindings public
> comments list.
>
> This is the agreed response of the technical committee as a whole and
> was approved unanimously at the meeting of the TC which took place on
> September 3rd 2009.
>
> ------------------------
>
> Thanks for taking the time to review the specification, sending your
> public review comment [1], and for sharing you thoughts. They are much
> appreciated.
>
> The public review comment at [1] suggests that: "... the work of
> defining a Web Service callback standard is best done by the appropriate
> Web Services working groups in OASIS in the broadest scope possible.
> This will foster a general interoperable mechanism for all architectures
> and programming models that use standard Web Services protocols on the
> wire."
>
> There is a misunderstanding on the commenter's part that the SCA Web
> Services Binding defines a (generally applicable) "Web Service callback
> standard." The binding defines an *SCA* Web service callback protocol
> standard that provides the wire-level details for implementing an SCA
> callback defined by the SCA Assembly specification [2]. [2] defines a
> callback mechanism that satisfies the needs of the SCA Assembly model
> and is not meant to satisfy general purpose callback requirements with a
> broadest scope possible. Furthermore, there does not exist any other
> OASIS Web Services Working Group or a Technical Committee that
> specializes in Web Services that has callbacks in its charter scope.
> This TC *does* specialize in Web services and is chartered to produce a
> Web services binding for SCA.
>
> This TC does believe that it should define an interoperable Web services
> protocol that implements SCA callback and it has done that. It does not
> believe that it is in the scope or interest of this TC to define a
> callback protocol for all architectures and programming models.
>
> WRT your comment about SCA Assembly specification Section 7.4, we
> respectfully request you to share that feedback with the SCA Assembly TC
> [3], as the SCA Assembly specification is not owned by and is not in
> scope for this TC.
>
> [1]
> http://lists.oasis-open.org/archives/sca-bindings-comment/200908/msg00000.html
>
> [2]
> http://docs.oasis-open.org/opencsa/sca-assembly/sca-assembly-1.1-spec-cd03.pdf
>
> [3] http://www.oasis-open.org/committees/tc_home.php?wg_abbrev=sca-assembly
>
> --------------------------
>
> Follow-up comments are welcome.
>
> Regards, Simon
>
> Simon Holdsworth
> STSM, SCA Bindings Architect; Master Inventor; OASIS SCA Bindings TC Chair
> MP 211, IBM UK Labs, Hursley Park, Winchester SO21 2JN, UK
> Tel +44-1962-815059 (Internal 245059) Fax +44-1962-816898
> Internet - Simon_Holdsworth@uk.ibm.com <mailto:Simon_Holdsworth@uk.ibm.com>
>
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